Radiation detection apparatus

ABSTRACT

A radiation detection apparatus having a hand-held radiation detection probe with a switch assembly removably mounted thereon is hereinafter disclosed. The switch assembly having first and second switches, one to initiate transmission of electrical signals representing scintillations detected over a set time period to a remotely located control unit for counting and averaging, and the other to direct the control unit to download and preferably record the counted and averaged scintillation values for further use. The switch assembly has an insulating member for electrically insulating the switches from the probe, and spaced gripping members that releasably grip the probe. A movable stand is provided preferably with a holder for holding the probe. The probe can have a protective cover thereon with a switch assembly mounted onto the probe over the cover.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a radiation detection apparatus.More particularly, the present invention relates to an apparatus fordetecting, quantizing and mapping radiation emitted from a scintillationfluid having gamma-emitting isotopes. The apparatus is battery operatedand has a hand-held probe for detecting radiation, and for transmittingelectrical signals that represent the detected radiation to a remoteunit to process the signals into information. The hand-held probe is ascintillation detector that has a switch assembly removably mounted onthe probe for initiating remotely electrical signals to a control unit.

[0003] The switch assembly has preferably two finger-operated triggers.One trigger initiates the count, and the other trigger directs theremote unit to download, and preferably record, the countedscintillations or averaged scintillation values for further use.

[0004] 2. Description of the Prior Art

[0005] Procedures for detecting, quantizing and localizing or mappingcarcinomas in living beings are known. A radiation-emitting substance ispassed through a patient's body. Either a radiation detector device issecured to the patient's body, or a hand-held probe is held adjacent aseries of sites surrounding a suspected tumor. One procedure involvesinjecting a scintillation fluid containing, for example, technetium 99,in quadrants of the capillary system located about a site to determinewhether cancer has spread to the lymphatic system. Since fluid drainsfrom the injected area through the lymphatic system, the scintillationdetector allows identification and location of the sentinel node, thefirst lymph node draining the most scintillation fluid and emitting thehighest number of scintillations in the lymphatic drainage path from thetumor.

[0006] Heretofore, each radiation detecting, quantizing and mappingapparatus has been connected by hardwire to an electrical receptacle orhas a battery that discharges during use. One conventional apparatus hasa foot pedal connected to a remote unit to initiate counts. The footpedal does not activate a downloading of counts, let alone during apreset time period. A second conventional apparatus has a built-inrechargeable battery. This is disadvantageous since an extended time,usually four to six hours, is required to recharge the battery. Sincerecharging cannot occur during operation of the apparatus, should thebattery require recharging during a procedure, the procedure must bestopped.

[0007] In addition, the apparatus has a hand-held probe and a remotelylocated control unit. The probe was merely used for detecting emittedradiation from the patient's body and transmitting electric signalsrepresenting the detected radiation to the control unit for processing.The control unit has the controls for controlling various functionsincluding taking counts, setting the time period for taking timedcounts, and initiating the taking of counts. These controls had to beactivated solely at the control unit. This is disadvantageous because toconduct the counting procedure, the operator must hold and use thehand-held radiation detection probe with one hand. With the other hand,the operator needed to reach the control unit and manipulate thecontrols. It is difficult to conduct both the detection and controlmanipulation simultaneously. Also, to do so results in difficulties intaking counts and, perhaps, inaccuracies in the counts. For example,while taking a scintillation count, the probe must be preciselypositioned over a selected site for a set period of time. It isdifficult to maintain that precise position while reaching to depress acount start button on the control unit. Movement of the probe duringcounting can create an inaccurate count. Since counting is repeated atdifferent probe angle positions over the same site and over differentbody sites, the difficulties and inaccuracies can be compounded.Therefore, it is desired to have an improved radiation detectionapparatus that obviates or reduces such difficulties, inaccuracies andinefficiencies.

[0008] It is known to employ switches removably mounted on a handpiece.U.S. Pat. No. 5,304,763 discloses two or more finger-operated-switchesremovably mounted to a hand-held electrosurgical device. The switchescontrol the application, e.g., initiation and termination, of electricalenergy provided to the device. For example, one switch controls theapplication of energy to energize an electrode of the device for cuttingbody tissue. The other switch energizes a suction portion of the deviceto remove cut tissue from the body.

[0009] Heretofore, hand-held radiation detection probes and their cableshave had to be sterilized to be re-usable because they becomecontaminated during use. Sterilizing such hand-held detection devicesprior to each use is expensive, time consuming and may requiremaintaining a larger than necessary inventory of the probes and cables.It is desired to have an apparatus that obviates the need forsterilizing hand-held devices or probes prior to their re-use. It wouldalso be desired to have an apparatus that allows for the use ofhand-operated switches mounted on the hand-held device or probe duringuse, but permits removal from it during sterilization of the device orprobe.

SUMMARY OF THE INVENTION

[0010] It is an object of the present invention to provide an improvedradiation detection apparatus that includes a hand-held radiationdetection probe with at least one switch removably mounted thereon.

[0011] It is another object of the present invention to provide such aradiation detection apparatus in which the one switch has a firsttrigger or button that remotely enables a counter in a control unit toaccumulate electrical signals representing radiation scintillationdetected over a set time period, and a second button that remotelydirects the control unit to ouput data regarding the countedscintillations.

[0012] It is still another object of the present invention to providesuch a radiation detection apparatus that allows the operator to operatea hand-held probe, while simultaneously using the switches mounted onthe probe to control a remote control unit.

[0013] It is yet another object of the present invention to provide sucha radiation detection apparatus in which the control unit is batteryoperated to provide total mobility of the control unit.

[0014] It is a further object of the present invention to provide such aradiation detection apparatus that has a removable, rechargeable batteryas its power source.

[0015] It is still a further object of the present invention to providesuch an improved radiation detection apparatus that enables a hand-heldradiation detection probe to be reused without prior sterilization.

[0016] It is yet a further object of the present invention to providesuch a hand-held radiation detection probe with a cover to protect theprobe from contamination during use, and to isolate electrically theswitch from the hand-held probe.

[0017] It is still yet a further object of the present invention toprovide such an improved radiation detection apparatus that is removablymounted on a movable stand.

[0018] These and other objects of the present invention are achieved bya radiation detection apparatus comprising: means for counting ascintillation count value; means for outputting a scintillation countvalue to a utilization device; a hand-held probe including ascintillation detector; means for connecting the probe to the countmeans; first means removably positioned on the probe for, in a firststate, causing the count means to accumulate a scintillation count overa first period, and in a second state, causing the count means toaccumulate a scintillation count over a second period, the second periodbeing longer than the first period; and second means removablypositioned on the probe for causing, upon activation, the output meansto manifest an accumulated scintillation count from the count means.

[0019] The radiation detection apparatus can include means fordisplaying a count value of the count means. The display means respondsto activation to the second state of the first means, by displaying acount value accumulated over the second period for a preset time period.

[0020] Preferably, activation of the second means is operative, onlyduring the preset time period, to cause the output means to manifest ascintillation count accumulated during the second period from thecounter means.

[0021] Activation of the second means, at times other than during thepreset time period, causes activation of any selected other function ofthe control unit.

[0022] The radiation detection apparatus can include a movable standhaving a holder for releasably mounting the probe on the stand.

[0023] The present invention also includes a hand-held radiationdetection probe having a flexible removable protective coveringthereover to protect the probe from contamination during storage or use,and permit the probe to be re-used without prior sterilization.Preferably, the covering is a sheath.

[0024] The present invention may further include a hand-held radiationdetection probe having a switch assembly removably mounted thereon. Theswitch assembly has at least one switch, an insulating member forelectrically insulating said switch from said probe which is a saddleformed by a spaced, opposed pair of cooperative depending grippingmembers adapted to releasably grip said probe therebetween.

BRIEF DESCRIPTION OF THE DRAWINGS

[0025]FIG. 1 is a schematic representation of the radiation detectionapparatus of the present invention;

[0026]FIG. 2 is a top plan view, with portions broken away, of apreferred embodiment of the probe shown in FIG. 1;

[0027]FIG. 3 is a top plan view, with portions broken away, of the probeshown in FIG. 2 without a switch mounted thereon and covered by asheath;

[0028]FIG. 4 is a top plan view, with portions broken away, of the probeshown in FIG. 2 covered by a sheath and having a switch assembly mountedthereon;

[0029]FIG. 5 is a top plan view, with portions broken away, of the probeshown in FIG. 2 covered by a drape and with a switch assembly shownoptionally mounted thereon;

[0030]FIG. 6 is a perspective view of the removable switch assembly thatis mounted on the probe shown in FIG. 2;

[0031]FIG. 7 is an exploded perspective view of the switch assemblyshown in FIG. 6;

[0032]FIG. 8 is a front view of the housing of the control unit of thepresent invention;

[0033]FIG. 9 is a front perspective view of a movable stand for mountingthe control unit of the radiation detection apparatus of FIG. 1; and

[0034]FIG. 10 is a rear perspective view, with portions broken away, ofthe control unit and stand shown in FIG. 9.

DETAILED DESCRIPTION OF THE INVENTION

[0035] Referring to the drawings and, in particular, FIG. 1, there is aschematic of a preferred embodiment of the radiation detection apparatusof the present invention, generally represented by reference number 10.Apparatus 10 includes a hand-held radiation detection device or probe50, and a control unit 100 connected to probe 50 by a suitableconnection, such as a flexible cable 12. Probe 50 includes a radiationdetector 52, a handle 54, and a shaft 56 that connects detector 52 tohandle 54. Detector 52 includes a crystal, such as a cadmium telluridecrystal, for detecting radiation, such as gamma protons, emitted from aradiation source in a patient's body. The radiation source is ascintillation fluid preferably containing technetium 99.

[0036] Probe 50 converts the detected scintillation radiation intoelectrical pulses that are amplified and transmitted through cable 12 tocontrol unit 100. Removably mounted to probe 50 is a switch assembly 70.Assembly 70 preferably has two switches 72, 74. Switches 72, 74 arepreferably push button switches.

[0037] Activation of switch 72 enables a count accumulator module 158,described below, to accumulate a scintillation count over a preset timeperiod, such as ten seconds. Otherwise, scintillation counts areaccumulated over succeeding one second periods. The scintillation pulsesdetected by probe 50 pass from the probe through cable 12 to a pulseshaping circuit 150 where the scintillation pulses are shaped. Theshaped pulses are fed to a discriminator 152 which passes pulses thatfall within an energy window that has been preset for technetium 99 byan energy window set 154. The pulses passed by discriminator 152 are fedto an audio unit 156 where they are broadcast to aid the probe operatorin positioning probe 50.

[0038] Pulses from discriminator 152 are also fed to a counter, forexample a count accumulator module 158. Module 158 counts thescintillation pulses and averages them, in the normal operational mode,over succeeding one second periods, or over a preset period, such as aten second period, if selected by the probe operator's activation ofswitch 72 instead of pressing button 108 on control unit 100. Theaccumulated and averaged count value is passed from count accumulatormodule 158 to a display unit 160 that displays the averaged count valuefor each one second period, or for the preset 10 second period.

[0039] Upon activation of switch 74 on probe 50, the accumulated andaveraged count value is also passed from module 158 through a downloadcontrol 162 and output to a terminal, here shown as output terminal 164.Output terminal 164 can be connected to a utilization device, such as arecorder 166. Output terminal 164 may also be connected, directly orremotely, to a computer 168. Computer 168 can be, for example, apersonal computer, laptop, or other computing device, for storage andmanipulation of the output data.

[0040] The electronic signals sent by control unit 100 to computer 168represents the ten second count frozen and shown on display 160. Signalsreceived by computer 168 will be received by its software which willrecord the signals, for example, to keep patient records of how controlunit 100 was used (settings, duration, etc.). The software can betailored to individual preferences or to established clinical protocols.However, control unit 100 and probe 50 must be kept electricallyisolated from computer 168, and the computer must not be able tocontrol, program or otherwise affect the performance of the control unitor the probe. Thus, a unidirectional (control unit 100 to computer 168)isolated interface, e.g. optical coupler (represented by the heavydashed line II) is employed should the computer be connected to outputterminal 164.

[0041] After a patient has been injected with a radiation emittingsubstance, for example, a scintillation liquid containing technetium 99,hand-held probe 50 is held stationary in position over a radiationdetection site on the patient's body. A count is taken of thescintillation detected at that site for a given time period. Thisprocess is repeated at one or more different sites, or for differentangular positions of the probe on the same site, and a comparison ismade of the counts obtained at each site. With switch 72 in adeactivated position, scintillations are detected or sampled over aseries of first count sampling periods. Each sample period is, forexample, preferably of one second duration. The signals or pulsestransmitted from probe 50 during each one second period cause countaccumulator module 158 to accumulate a scintillation count that is anaverage of the scintillation pulses over the one second period.

[0042] Control unit 100 is set such that activation of switch 72initiates a ten second count sampling period, followed by a three secondfreeze period of the average count taken for the ten second period.During the ten second sampling period, module 158 accumulates andaverages the scintillation counts taken over the ten second period. Theaverage count is displayed on display 160 for the three second freezeperiod. During the sampling period, a sampling light (not shown) oncontrol unit 100 will flash. At the end of the sampling period, thesampling light goes off and a single audible beep is emitted. If, duringthe three second freeze period, switch 74 is activated by the operator,the frozen count is downloaded from module 158 to output terminal 164which sends the frozen count to a utilization device.

[0043] When switch 74 is activated during the three second period, twoaudible beeps are emitted. If switch 74 is not activated during thefreeze period, no downloading of the frozen count occurs. Switch 74 canbe activated during or at the end of any one second count samplingperiod or, as stated above, during the three second freeze period. Thus,activation of switch 74 downloads the ten second count value to outputterminal 164, and an audible signal indicates that the download hasoccurred. If switch 74 is not activated during the three second freezeperiod, module 158 returns to its normal mode of accumulating andaveraging sampled counts per second and displaying the counts per secondon display 160.

[0044] Control unit 100 is powered by a removable, rechargeable battery.The preferred battery is a lead-acid rechargeable battery capable offour hours of continuous operation. When a predetermined set period oftime of power battery life remains, such as, for example, fifteenminutes, a warning indicator, such as a light, will flash or indicatethe commencement of that set period.

[0045] Accordingly, the user can simply insert a second battery in thecontrol unit 100 to operate the control unit, and the first battery cansimply be recharged when desired.

[0046] As shown in FIG. 2, switch assembly 70 is removably mounted onhandle 54 of probe 50. Switch assembly 70 preferably has twofinger-operated push button switches 72, 74.

[0047] Referring to FIG. 3, probe 50 may have a removable protectivecover 60 placed thereover. The protective cover 60 preferably is asheath that substantially fully encompasses probe 50 to protect it frombeing soiled or contaminated during storage and use. Sheath 60 permitsprobe 50 to be re-used without prior sterilization. Sheath 60 has aclosed end 62 that covers detector 52, and an opposite open end 64 thatcan be at any desired location beyond handle 54. Preferably, sheath 60is long enough to the entire length of cable 12, as shown in FIG. 2.

[0048] Sheath 60 can have any suitable size, shape and configuration.Thus, it can fit loosely, tightly or form-fitted or even shrunk ontoprobe 50. As shown in FIG. 4, sheath 60 preferably fits sufficientlytightly onto probe 50, especially about detector 52, to minimizeinterference with its function. Sheath 60 preferably also fits tightlyabout the portion of handle 54 onto which switch assembly 70 is to bemounted, to enable the switch assembly to remain tightly and securelymounted onto the handle. Sheath 60 can be made of any suitable materialor materials, and can be single or multiple layered.

[0049] Preferably, sheath 60 is made from a flexible film or sheet. Thepreferred material for sheath 60 is a single layer of polyurethane.

[0050] Although sheath 60 is the preferred cover, any suitable cover canbe employed that permits switch assembly 70 to be effectively mountedonto probe 50. The sheath 60 is removable and preferably disposable andeasily replaceable. Thus, as shown in FIG. 5, a drape 66 of flexiblefilm can be placed over and secured to probe 50. As shown in FIG. 5, acontinuous portion of drape 66 can be placed over detector 52, tiedaround shaft 56 by a tie 68, and gathered and secured about handle 54 orabout cable 12 (not shown) by any suitable member, such as by a clip 69.Switch assembly 70 (dashed line) can be mounted on probe 50 awhile theswitch assembly is covered by drape 66.

[0051] Referring to FIG. 6, switch assembly 70 preferably has a saddle76 formed by a curved undersurface 78 and a pair of spaced opposedcooperative depending gripping members 80 that are adapted to releasablygrip probe 50 (not shown) between them. Gripping members 80 arearcuately shaped and sized to fit tightly about handle 54 of probe 50.Gripping members 80 are rigid enough to hold probe 50 between them, butresilient enough to allow the switch assembly 70 to be removed from theprobe.

[0052] As shown in FIG. 7, the preferred switch assembly 70 also has acover 82, button switches 72, 74, a carrier in the form of a mountingmember 84 having saddle 76, a recessed panel 86, and an insulatingmember 88 that fits into recessed panel 86 and insulates the switchesand any electrical wiring and connections (not shown) from probe 50 (notshown). In a preferred embodiment, there are two switches 72, 74.However, it is possible that these switches may be combined into asingle switch or that a third or more switches may be added to controlremotely other functions of control unit 100.

[0053] Referring to FIG. 8, housing 212 of control unit 100 has a powerbutton 102, a plurality of holes 104, preferably three, for operativelyreceiving a three prong plug of cable 12, a receiver 106 for operativelyreceiving a plug connected to probe 50, and a digital display 130.Housing 212 also has a button 108, which is preferably a push button,that initiates the ten second count time period, a light 110 that lightsduring the ten second period, a calibration indicator 112, and a batterycharge indicator light 114. Housing 212 also has a volume control knob116, a plurality of volume indicators 118, preferably light indicators,a knob to deactivate an internal threshold and window pre-set fortechnetium 99 to permit setting a wider window, a light indicator 122for the internal threshold, and an audio range knob 124 to change theaudio range from among the three values indicated by lights 126, 128 and130. Referring to FIGS. 6 and 8, when switch 72 of switch assembly 70 isactivated, button 108 is activated and, thus, light 110 is activated.When switch 74 is activated to download or record a count, an audiblesignal is provided.

[0054]FIGS. 9 and 10 show a movable stand 200 suitable for use withradiation detection apparatus 10 of the present invention. Stand 200 hasan upper vertical shaft 202 telescopically seated with a lower verticalshaft 204. Shaft 204 is mounted at its bottom end onto the hub of aplurality of radially outwardly extending legs 206 supported onrotatable wheels 208. Shaft 202 is held at a desired height by anadjustable restrainer 205 on the top end of shaft 204. The upper end ofshaft 202 has an adjustable fastener 210 mounted thereon. Fastener 210has a horizontal shaft (not shown) onto which the lower end 211 of abracket 214 is rotatably mounted. A housing 212 of control unit 100 issecured to bracket 214. Bracket 214 and housing 212 can be tilted up anddown to a desired angle about the shaft of fastener 210 and held at thedesired angle by tightening threaded bolt 215.

[0055] Lower shaft 204 preferably has a pair of holders 220 mountedthereon. Each holder 220 has a pair of spaced, vertically disposedopposed holding members 222 adapted, e.g. shaped, to receive andreleasably hold probe 50. Each holder 220 is positioned within aprotective box 224 having a cover 226. Lower shaft 204 preferably has asupport 228 for supporting cable 12 for probe 50. Onto the rear of lowershaft 204, there is preferably fixedly mounted the lower end of anelongated bracket 230. Bracket 230 has a platform 232 welded orotherwise fixed thereto. Platform 232 preferably is for supporting anauxiliary component such as a computer (not shown). The side of housing212 has an angularly disposed rectangular cavity at 234 for holding andaccessing the replaceable rechargeable battery (not shown) to supplypower to control unit 100.

[0056] The present invention having been thus described with particularreference to the preferred forms thereof, it will be obvious thatvarious changes and modifications may be made therein without departingfrom the spirit and scope of the present invention as defined in theappended claims.

1-20. (canceled).
 21. A radiation detection apparatus comprising: ahand-held probe having a scintillation detector; a counter operablyconnected to said hand-held probe for counting first and secondscintillation count values; a control device for outputting at least oneof the scintillation count values to a utilization device; a displayoperably connected to said counter for displaying at least one of thescintillation count values; and a switch assembly adapted to beremovably mounted to said hand-held probe and including first and secondswitches, said first switch in a first state remotely causing saidcounter to accumulate said first scintillation count value and in asecond state remotely causing said counter to accumulate said secondscintillation count value, said second switch in a first state remotelycausing said first scintillation count value to be communicated to saidutilization device and in a second state remotely causing said secondscintillation count value to be communicated to said display.
 22. Theradiation detection apparatus of claim 21, wherein said firstscintillation count value is accumulated over a first time period. 23.The radiation detection apparatus of claim 22, wherein said secondscintillation count value is accumulated over a second time period. 24.The radiation detection apparatus of claim 23, wherein said first timeperiod is greater than said second time period.
 25. The radiationdetection apparatus of claim 21, wherein said switch assembly furtherincludes a carrier formed from a mounting member having a saddle, saidsaddle including a pair of cooperative depending gripping membersadapted for releasably mounting said switch assembly to said hand-heldprobe.
 26. The radiation detection apparatus of claim 21, wherein saiddisplay displays said second scintillation count value for a preset timeperiod.
 27. The radiation detection apparatus of claim 26, wherein saidsecond switch is in said first state during said preset time period andcauses said control device to output said second scintillation countvalue accumulated during said second time period from said counter. 28.The radiation detection apparatus of claim 26, wherein said preset timeperiod is about three seconds.
 29. The radiation detection apparatus ofclaim 21, wherein said control device downloads to said utilizationdevice through an electrically isolating interface that precludesreverse signal transfer from said utilization device.